How to Get Rid of Ants in the Garden Fast
Key Takeaways
- ✅ Most common species: Black garden ants are the UK’s most common; colonies typically have 4,000–15,000 workers.
- ⏱️ Natural baits work quickly: Borax and sugar (1:3 ratio) usually eliminate colonies within ~7 days.
- 🧭 Trail disruption: Vinegar solutions break down pheromone scent trails that guide workers.
- 🌿 Repellents: Coffee grounds and cinnamon can help deter ants thanks to strong aromas.
- 💧 Irrigation helps: Regular watering discourages nests in pots, as ants prefer dry media.
- ⚠️ Dry kill method: Diatomaceous earth (DE) dehydrates ants—apply only on dry soil.
- 🛡️ Prevention wins: Exclusion and hygiene are vastly more effective than repeated treatments.
- 🐞 Ants can be beneficial: They aerate soil and help control certain pests (e.g., aphids).
Why Ants Come to Your Garden
Ants do not appear at random. They are seeking two things: food and suitable nesting sites. Understanding these drivers makes control far more effective.
Foraging workers travel along established trails, clustering around sweet food sources such as fallen fruit, aphid honeydew, pet food left outdoors, and poorly managed compost. Black garden ants will also enter homes—especially kitchens—in warm weather when scouts search for new resources.
Timing matters: mating flights for males and virgin queens usually occur between June and September during warm, still days—so expect visible spikes in activity then.
Weather plays a key role. Ants favour dry nesting conditions, so you’ll notice more anthills during dry spells. Many gardeners attempt to pour boiling water into entrances, but without targeting the whole colony, results are often short-lived.
Kill the Colony with Baits
Baiting is the most reliable long-term control. For tough infestations, sugar-and-borax baits can wipe out a colony in roughly a week.
Make a Borax and Sugar Bait
Use a 1:3 ratio of borax to sugar. Mix 1 tsp borax with 3 tsp icing sugar, then add a few drops of water or honey to form a paste. (A larger batch might be ½ cup water + ½ cup sugar + 1½ tsp borax.)
Place small amounts on bottle caps or shallow lids along ant trails and near nest entrances. The sugar lures workers; they ingest some and carry the rest back for the queen and brood.
Use Baking Soda and Sugar
As a gentler option, mix equal parts baking soda and icing sugar. The sugar attracts; the baking soda disrupts digestion. It’s slower than borax but safer around households.
Offer in shallow lids along trails and refresh every few days or after rain.
Place the Bait Strategically
Location is everything. After observing ant movements for 24 hours, position baits on the busiest routes, by nest entrances, and in cracks/crevices. Do not combine baits with sprays or dusts—repellency will stop ants from taking the bait.
Eliminate and Deter Ants Naturally
Natural methods work by disrupting communication (pheromone trails) and making your garden less attractive to scouts.
Use a Vinegar Solution
Mix equal parts white vinegar and water in a spray bottle, then treat trails, entry points, and around nests. The acetic acid helps neutralise the scent marks ants use for navigation. Reapply after rain.
Clean with Soapy Water
Combine 2 tbsp washing-up liquid with 1 litre of water. This kills on contact and wipes away scent trails. The surfactants compromise the waxy cuticle, leading to dehydration.
Use Natural Repellents
Sprinkle cinnamon, citrus peel, or coffee grounds near nests and along likely approaches—these strong aromas can mask pheromones and nudge ants elsewhere. Cayenne pepper lines may also deter crossings. Results vary, so pair with baits for best effect.
Advanced Natural Methods
Diatomaceous Earth (DE)
Food-grade DE is a fossil algae powder that kills via desiccation. Lightly dust dry soil on trails and around nest areas. Reapply after rain or irrigation.
Boiling Water
Pour into visible surface entrances for immediate knockdown. Colonies are often deeper/wider than they appear, so repeat treatments may be needed. Avoid plant roots.
Beneficial Nematodes
Steinernema feltiae can be watered into lawns and borders to attack ant colonies. Works best in consistently moist soil; follow supplier directions.
Safe for pets, children, and non-target wildlife.
Prevent Future Infestations
Keep Surfaces Clean
Store all foods (including pet food) in sealed containers and clean up residues immediately. Wipe prep areas with vinegar solution to remove attractants.
Seal Entry Points
Fill cracks in masonry, seal gaps around pipes and cables, and fit tight brush seals to doors. Weather-strip windows and check foundations periodically for new gaps.
If using residual insecticides, professionals focus on strategic points (doors, vents, ducts, drains) for an enduring barrier—avoid DIY overuse.
Remove Food Sources
Clear pet feeding areas daily, store feed securely, and remove fallen fruit promptly. Keep compost lids tight and turn contents regularly to reduce attractiveness.
Companion Planting for Ant Control
Some plants help indirectly by reducing aphids (and thus honeydew), or by strong scents near entrances and patios. Try borders or pots of:
- Mint, lavender, rosemary: aromatic deterrents along paths and thresholds
- Wormwood (Artemisia absinthium): strongly scented; helps reduce aphid pressure
- Garlic: sulphur compounds can discourage activity near beds
Consider a scented “herb moat” around veg beds or seating areas.
Guide: 25 Unusual and Exotic Things to Grow in a Greenhouse
Understanding UK Ant Species
Black Garden Ant (Lasius niger)
Workers ~3 mm; colonies up to ~15,000 (typically 4,000–7,000). Common outdoors April–October, peaking in warm spells. Harmless; no sting.
Yellow Meadow Ant (Lasius flavus)
Small (2–4 mm). Makes low mounds in lawns; mostly subterranean foragers. Rarely enters houses.
Red Ants (Myrmica spp.)
Reddish-brown (4–6 mm). Can sting (usually mild). Often under stones and logs; less common in domestic gardens.
When Professional Help is Needed
Call in professionals if natural methods fail or when:
- Estimated populations exceed ~40,000 per colony or multiple colonies exist
- Nests threaten structures or cause persistent contamination
- Residents experience allergic reactions to stings
Seek BPCA-certified technicians for species-specific, family-safe solutions. Expect residential treatments roughly £150–£300, depending on severity and property size, often with guarantees.
Equally, remember the ecological role of ants—RHS guidance suggests tolerance where practical; reserve control for genuine problems.
For greenhouse pest hygiene, see How to Grow Seeds in a Greenhouse.
Frequently Asked Questions
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What is the best homemade ant killer?
Borax + sugar (1:3) paste placed along trails. Workers share it with the queen; most colonies collapse within ~7 days.
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What do ants hate the most?
Strong, acidic or aromatic scents that disrupt trails: vinegar, cinnamon, citrus peel, and coffee grounds can all help as deterrents.
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How do I get rid of ants in hours?
For immediate knockdown, use boiling water on visible entrances and soapy water spray on trails. Follow up with baits for lasting control.
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Does vinegar kill ants?
It can kill on contact and, more importantly, neutralises pheromone trails. Use equal parts white vinegar and water; reapply after rain.
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How long do natural methods take?
Baits: 3–7 days for colony collapse. Repellents work immediately but need reapplication. DE is quickest on dry surfaces.
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Are ants beneficial to gardens?
Yes. They aerate soil, scavenge pests, aid decomposition, and can support pollination via seed dispersal. Control only when they’re genuinely problematic.
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Can I use natural methods around pets and children?
Vinegar, coffee grounds, and cinnamon are generally low risk. Handle borax with care: wear gloves and keep baits inaccessible.
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Why do ants keep coming back?
Food remains available and entry points persist. New queens often recolonise cleared areas. Prevention (hygiene + exclusion) is key.
